From patchwork Fri Jul 22 11:07:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoshihiro Shimoda X-Patchwork-Id: 12926370 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED0A7CCA48C for ; Fri, 22 Jul 2022 11:08:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234548AbiGVLIE (ORCPT ); Fri, 22 Jul 2022 07:08:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234301AbiGVLIA (ORCPT ); Fri, 22 Jul 2022 07:08:00 -0400 Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8C88BA896D; Fri, 22 Jul 2022 04:07:59 -0700 (PDT) X-IronPort-AV: E=Sophos;i="5.93,185,1654527600"; d="scan'208";a="128784530" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie6.idc.renesas.com with ESMTP; 22 Jul 2022 20:07:57 +0900 Received: from localhost.localdomain (unknown [10.166.15.32]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id B5FB541FF8A7; Fri, 22 Jul 2022 20:07:57 +0900 (JST) From: Yoshihiro Shimoda To: lpieralisi@kernel.org, robh+dt@kernel.org, kw@linux.com, bhelgaas@google.com, krzk+dt@kernel.org, geert+renesas@glider.be, magnus.damm@gmail.com Cc: marek.vasut+renesas@gmail.com, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda Subject: [PATCH v4 07/12] PCI: dwc: Avoid reading a register to detect whether eDMA exists Date: Fri, 22 Jul 2022 20:07:39 +0900 Message-Id: <20220722110744.2274466-8-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220722110744.2274466-1-yoshihiro.shimoda.uh@renesas.com> References: <20220722110744.2274466-1-yoshihiro.shimoda.uh@renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Since reading value of PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL was 0x00000000 on one of SoCs (R-Car S4-8), it cannot find the eDMA. So, directly read the eDMA register if edma.red_base is not zero. Signed-off-by: Yoshihiro Shimoda --- drivers/pci/controller/dwc/pcie-designware.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index e04128a22bbe..8a274953e25d 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -839,8 +839,7 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci) { u32 val; - val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL); - if (val == 0xFFFFFFFF && pci->edma.reg_base) { + if (pci->edma.reg_base) { pci->edma.mf = EDMA_MF_EDMA_UNROLL; val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL); @@ -848,6 +847,7 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci) pci->edma.mf = EDMA_MF_EDMA_LEGACY; pci->edma.reg_base = pci->dbi_base + PCIE_DMA_VIEWPORT_BASE; + val = dw_pcie_readl_dbi(pci, PCIE_DMA_VIEWPORT_BASE + PCIE_DMA_CTRL); } else { return -ENODEV; }